Known in the art is a catalyst of liquid-phase oxidation of sulfur-containing compounds containing as active components hard coal ash and cobalt phthalocyanine and a thermoplastic polymer, in particular, polyethylene as a carrier, with the following proportioning of components, in % by mass:
______________________________________ hard coal ash 40-50 cobalt phthalocyanine 1-5 thermoplastic polymer the balance (SU, A, 1154772). ______________________________________
The prior art catalyst referred to above has a comparatively high catalytic activity and selectivity with respect to sulfur both in the purification of effluents containing hydrogen sulfide in an amount of up to 100 mg/l and in the regeneration of absorbing solution used for the purification of a production gas from hydrogen sulfide with a hydrogen sulfide content in the gas of up to 0.5% by vol. when pH of the oxidized solutions is maximum 8.0. Thus, in oxidizing 110 mg/l of hydrogen sulfide in effluents in the presence of the prior art catalyst during ten minutes with the air supply rate of 50 cm.sup.3 per 1 mg of hydrogen sulfide at a gauge pressure of 0.3 MPa and at 20.degree. C. and pH of 7.5; 8.5; and 9.5 the degree of oxidation of hydrogen sulfide is 98.5; 92.2; and 97.7%, respectively. In oxidizing 1020 mg/l of hydrogen sulfide under the abovementioned conditions, the degree of oxidation of hydrogen sulfide decreases to 96.8; 97.2; and 89.7%, respectively. Complete oxidation of 110 mg/l of hydrogen sulfide in effluents with their pH of 7.5 and 8.5 was achieved in 12-15 minutes and in 23-25 minutes with pH of 9.5. With a content of hydrogen sulfide in effluents of 1020 mg/l complete oxidation of hydrogen sulfide at pH of 7.5 and 8.5 is achieved in 23-25 minutes and in 40-45 minutes with pH of 9.5.
The prior art catalyst is also deficient in that it incorporates an expensive active component--cobalt phthalocyanine which is used in rather high concentrations (up to 5% by mass). It is, therefore, desirable to make use of a cheaper catalyst which is at least as active as the prior art catalyst for organizing commercial purification of effluents.
Also known in the art is a catalyst of liquid-phase oxidation of sulfur-containing compounds containing as an active component hard coal ash and a thermoplastic polymer such as polyethylene as a carrier, with the following proportioning of components, in % by mass:
______________________________________ coal ash 40-50 thermoplastic polymer the balance (SU, A, 1057096). ______________________________________
The prior art catalyst has a high enough catalytic activity. Thus, complete oxidation of hydrogen sulfide in formation fluid with a starting concentration of 90 to 110 mg/l, at a rate of oxidant (air) supply of 100 cm.sup.3 per 1 mg of hydrogen sulfide at 20.degree. C. and at the pressure of 0.3 MPa occurs during 30 minutes of oxidation.
In carrying out a production process using prior art catalysts, large-size industrial installations have to be constructed so as to result in an increase in capital investments and operation cost.
A highly-active and polyphase catalyst is needed for the purification of effluents containing, in particular, hydrogen sulfide over a broad range of concentrations and pH values, which should be capable of sorbing oxygen at one of its phases and a sulfur-containing component at the other phase while ensuring their activation and supply to active centers of the catalyst.
The catalyst should also ensure a stable and high overall oxidation rate over a wide range of pH values and compsotiion of sulfur-containing compounds and their mixtures fed for oxidation.